Modern fighter aircraft use conductive filled polymer resins on the Outer Mold Line (OML) surface to address electromagnetic interference (EMI), facilitate electrostatic discharge (ESD), and to help control critical survivability characteristics of the vehicle. In order to achieve the necessary properties for this class of materials, nickel is used due to its conductivity, environmental stability, and low cost.
In order to meet the Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) for nickel, factory personnel utilize personal protective equipment (PPE), specialized finishing equipment, and specialized facilities that can store and properly dispose of nickel containing waste. All nickel-containing conductive materials have an exposure risk and require proper handling and procedures to ensure factory worker and maintainer safety. The known health risks associated with nickel are nickel dermatitis and nickel sensitization. Approximately 20% of the population has nickel allergies that will result in nickel dermatitis and prolonged exposure to nickel can result in nickel sensitization among those who do not have nickel allergies. Additionally, metallic nickel is reasonably anticipated to be a human carcinogen per the Twelfth Report on Carcinogens (2011). The Occupational and Safety Health Administration has set the permissible exposure limit (PEL) at 1 mg/m3 time weighted average (TWA) or an 8 hour work day during a 40 hour work week. The National Institute for Occupational Safety and Health (NIOSH) has set the recommended exposure limit (REL) at 0.015 mg/m3 TWA.